Hreflang Checker Pro

Hreflang Checker Pro is the most complete hreflang audit tool available as a Chrome extension. Built for SEO professionals, technical SEOs, international SEO specialists, and webmasters managing multilingual and multi-regional websites, this extension gives you a full diagnostic of every hreflang tag on any page — in seconds. No login. No account. No data sent to any server. Everything runs locally in your browser. 🌐 WHAT IS HREFLANG AND WHY DOES IT MATTER? Hreflang is an HTML attribute used to tell search engines like Google which version of a page to serve to users based on their language and region. When implemented correctly, hreflang signals help your international pages rank in the right countries and languages. When implemented incorrectly, it causes duplicate content confusion, ranking drops, wrong-language pages appearing in search results, and wasted crawl budget. Common hreflang mistakes include: Missing self-referencing hreflang tags Missing x-default tags Invalid ISO 639-1 language codes Broken reciprocal (return) links between language variants Relative URLs instead of absolute URLs Duplicate language codes on the same page HTTP errors (404, 301, 500) on linked hreflang target pages JavaScript-injected hreflang that search engines cannot reliably read All of these are exactly what Hreflang Checker Pro is designed to detect. ✅ CORE FEATURES ▸ COMPLETE HREFLANG TAG AUDIT Scans every <link rel="alternate" hreflang="..."> tag on the current page and presents them in a clean, sortable table. See the language code, target URL, HTTP status, and return link status for every tag at a glance. ▸ RECIPROCAL LINK VALIDATION One of the most critical — and most overlooked — hreflang requirements is that every linked page must link back to the original. Hreflang Checker Pro automatically fetches each target URL and checks whether it contains a return link pointing back to the current page. This is the same validation process used by professional SEO audit platforms, now available as a free browser extension. ▸ LIVE HTTP STATUS CHECKING Each hreflang target URL is checked for its HTTP response code. The extension clearly flags 200 OK, 301/302 redirects, 404 not found, 500 server errors, and network failures — so you can immediately see which language variants are broken or redirecting to unintended destinations. ▸ SSR vs JS DETECTION A critical but often-missed issue: hreflang tags that are injected by JavaScript rather than present in the raw server-rendered HTML may not be reliably picked up by Google. Hreflang Checker Pro detects whether each tag is server-side rendered (SSR) or JavaScript-injected (JS) and badges each row accordingly. If your tags are JS-injected, this is an important signal to investigate. ▸ LANGUAGE CODE VALIDATION The extension validates every hreflang attribute value against the full ISO 639-1 language code list, including regional variants (e.g. en-GB, zh-TW, pt-BR) and the special x-default tag. Invalid or misspelled language codes are immediately flagged as errors. ▸ SELF-REFERENCE DETECTION Google requires that hreflang tag sets include a self-referencing tag — a tag pointing back to the current page itself. Missing self-references are one of the most common hreflang implementation mistakes. The extension detects this instantly and flags it as a warning. ▸ X-DEFAULT DETECTION The x-default tag tells Google which page to serve when no other language variant matches a user's preference. Hreflang Checker Pro checks whether your tag set includes an x-default entry and flags it as missing if not present. ▸ RELATIVE URL DETECTION Hreflang URLs must be absolute (e.g. https://example.com/en/), not relative (e.g. /en/). The extension detects all relative hreflang URLs and flags them as warnings, since relative URLs may cause incorrect canonicalization in some implementations. ▸ DUPLICATE LANGUAGE CODE DETECTION Having two or more hreflang tags with the same language code on a single page is an implementation error that can confuse search engines. The extension detects all duplicate lang codes and reports them as errors. ▸ ISSUES TAB WITH CATEGORISED ERRORS AND WARNINGS Every detected problem is listed in a dedicated Issues tab, clearly separated into Errors (critical issues) and Warnings (best-practice violations). Each issue includes the specific language code it relates to, making it easy to know exactly what to fix. ▸ REAL-TIME PROGRESS INDICATOR As the extension checks reciprocal links in the background, a live progress bar shows how many URLs have been verified so far. You can see results updating in real time as each check completes. ▸ DYNAMIC TOOLBAR ICON STATES The extension icon in your Chrome toolbar changes colour based on the audit result — giving you an at-a-glance status on every page you visit: – Grey — scanning, or no hreflang tags found on this page 🟢 Green — all hreflang tags valid, no issues detected 🟠 Orange — warnings (e.g. missing x-default, redirects) 🔴 Red — errors (e.g. invalid lang codes, missing return links, HTTP errors) ▸ SORT AND FILTER Sort the tag table by: Default order, Language code (A–Z), HTTP Status, Return link status, or Issues First. Filter by language code or URL using the live search bar. Makes it easy to zero in on specific languages or problems in large hreflang sets. ▸ CSV EXPORT Export the full hreflang audit to a CSV file with a single click. The export includes all tag data: language code, raw URL, resolved URL, render source (SSR/JS), self-reference flag, validity flag, HTTP status, return link status, redirect flag, and any error messages. The filename is automatically set to include the hostname and date (e.g. hreflang-apple.com-2026-03-24.csv), making it easy to save and share audit reports with clients or team members. ▸ SETTINGS — CUSTOMISE YOUR WORKFLOW • Toggle auto-checking of reciprocal links on or off • Adjust the number of concurrent requests (1–10) for return link checking • Toggle row highlighting …